Apparatus for galvanizing rods



2 Sheets-Sheet l A. S. MOORE APPARATUS FOR GAILVANIZING RODS Filed Dec.2, 1942 n W n 4 u I M M. n u u a w u h u THHHIIIIIIIIIIIII'IIIH'IJHHHIIH,7. a Q m N u m m u w N u N fix X m \w I i j lm l H H if f :6 \YKNKW Q hM R w Sept. 5, 1944.

2 Sheets-Sheet 2 A LL M Sept. 5, 1944. A. s. MOORE APPARATUS FORGALVANIZING RODS Filed Dec. 2, 1942 threads with spelter.

f Patented Sept. 5,1 1944 UNITED STATES PATENT OFFICE I Armrmc RODS.

Allen S. Moore, Lebanon, Pa., asslgnor to Bethlehem Steel Company, acorporation of Pennsylvania Application December 2. 1942, Serial No.467,618

10 claims. (CL ill-59.4)

r of rusted threads may result in thread galling My invention relates toan apparatusfor coating uniformly rod-like or tubular objects, and moreparticularly it relates to an apparatus for the uniform and economicalgalvanizing of metal lic sucker rods.

1 Oil we1l sucker rods of the double pin and coupling type are straightsteel rods, usually 25 or and imperfect shouldering of the joint.Surplus zinc in the threads will interfere with attaching couplings, sothat when the threads are clogged with zinc the only way to obtainusable threads is to "bump" them, i. e., to rap or knock them against ahard surface to remove the excess spelter. This additional step meansextra expense and labor and may even shorten" the life of the rod, forundue hammering may deform the thread or cause cracks that radiate out;from the point of the blow and extend for considerable depths steelsemploying rather costly alloying elements,

vsuch as molybdenum, chromium, manganese and nickel, which are now underwar priorities and practically unobtainable. For very deep or highlycorrosive wells, there is at present no satisfactory substitute for thehigh strength and corrosion resistance of these alloy steels, butgalvanized rods of ordinary carbon steel may serve quite successfullyunder less extreme conditions,

provided only that the protective zinc coating is' as strongly adherentand ductile and as uniform in thickness as possible.

There are two methods of galvanizing in common use, viz., theelectrogalvanizing process and the hot-dip process.- The cold coat ngapplied by an electrolytic process is generally uniform, whenwellapplied, and the thickness is easily regulated' by varying eitherthe current density or the time of deposit. but the reduction in outputcompelled by the time factor, and the requirements of expensiveelectrical equipment and cur-.

rent, make this process uneconomical commercially. 4

Zinc coatings applied by the hot-dip process.

' on the other hand, are relatively free of the type on the, surface ofthe rod, making thecoating rough and uneven and filling the roots of theSuch a coating represents an actual waste of zinc, for the durability ofan unevenly applied coating is determined-by the thinnest part of thecoating and not by the thickest part.

Any defect or deficiency in the zinc coating will permit quick rusting,even'before use, and very badly rusted threads can obviously destroybelow the surface. A smooth, uniform coating over the threads and bodyof the rod is thus about the best obtainable insurance againstearlyoperating failure ofa string of galvanized sucker rods.

apparatus for producing a' hot-dip galvanized coating which will be,smoothly and uniformly distributed over the galvanized article.

I "Another .objectis an apparatus for procuring" more evenly andcompletely coated threads.

Still another object is an apparatus adapted. for covering. rod-like ortubular articles of metal with atighter and more ductile zinc coatingwhich will not flake or crack off under stress. I

' Other and further objects will appear hereinafter in the specificationand appended claims. Having thus given a general description of theadvantages and objects of my invention, I shall now in order to make thesame more clear, refer to, the annexed two sheets of drawings forming apart of this specification, and inwhich like characters of referenceindicate likeparts.

-.Figure 1 ,is a side elevation of the apparatus of my invention, andshowing its relation to the galvanizing and quenching tank; Fig. 2 isatop plan view thereof;

Fig. Sgis a, front elevation showing 'in'detail the self dju'sting guideroller device which permits the passage of the enlarged portions of thev sucker rods;

Fig. 4 is a side elevation of the guide roller device shown in Fig. 3;and

Fig. 5 is a horizontal section of a portion of the mounting of the guideroller device taken. on

all the usefulness of the rod, for the making 'up 55 cates a sucker rod,2 one end of a'conventional galvanizing tank, which is a long shallowpan filled with molten zinc or spelter, 3 a base mounted in skewedrelation at the exit end of said tank, 4 an electric motor fastened tothe base,

'5 the drive shaft of the. motor, 6 a pinion on shaft5, and I anengaging gear mounted on and driving a shaft'l. Said shaft 8 drivesthrough gears, 9,10 and II the magnetic rolls i 2 and I3 journalled inbearings l4, l5, l6 and II in end m'ountings l8 and IS. The magneticflux which -magnetizes said rolls emanates from the magat an angle ofabout 45 toward the advancing sucker rod I, and mounted on fittings 25which are preferably of brass or copper or the like to insulate fromstray magnetic flux. Said fittings 25 and 26 connect through pipe 2'!equipped with valve 28 to any suitable source of heated and 39 midwaybetween the two magnetic rolls I2 and I3 insures the proper directionand contact of the rod as it rotates and moves forward over said rollsl2 and I3.

The rotation of the rolls I2 and I3 then carries the rod I forwardthrough the second air ring 24 up th incline ll over the rollers 43 ontoconveyer trough 42. Air is blown from the air rings 23 and 24 at apressure of 25 to 80 pounds per square inch, and is preheated to atemperature high enough to prevent too rapi cooling of the zinc. Thevariation of air pressur and temperature controls the thickness of thezinc I coating on the rod and can be regulated to suit compressed air(not shown) As the galvanizing tank 2 will be kept heated in the usualpractice by a series of gas flames (not shown) within side burnercompartment 28, the air under pressure may be heated conveniently, forexample. by running the connecting pipe 21 from th compressor or othersource through said gas flames, or if desired, through the moltenspelter itself.

To insure the proper direction and contact of the rod l as it rotatesand moves forward over the rolls l2 and I3, a guide device is providedwhich comprises a pair of mountings of brass or other non-magnetic metalsecured by bolts 3| to the-base 3, between sald rolls l2 and I3, andhaving grooved slideways 32 to permit a limited amount of verticalmovement to perforated blocks 33 keyed thereinto and normally held inplace by vertical threaded rods 34, springs 35, and adjusting nuts 36.connected by a transverse haft 31, held in place by cotterpins 38 andhaving mounted thereon a grooved idle roller 39.

Adjacent thereto is the conventional elongated quenching tank 40, onwhich is mounted the incline 4i and pivoted conveyor trough 42, thelatter being provided with a plurality of aligned idle rollers 43 likethe one shown and an end stop (not shown) which may actuate an automatickicker (also not shown) to dump the galvanized rod I into the quenchingtank 40.

In the operation of my invention, any traces of rust and mill scalewhich may be present on the rods l are removed by pickling in a hotdilute acid solution, and washing with clean watel. Then the rods l arefluxed in a hot solution of zinc ammonium chloride, and dipped into Saidblocks 33-are the molten spelter in th galvanizing tank 2.

The spelter is kept at a temperature between 790 F., and 870 F., theperiod of immersion therein being determined by the size of the rods andthe weight of zinc coating desired, and the rods are kept from contactwith the pasty zinc iron dross which collects upon the bottom of thegalvanizing tank 2 by resting in a suspended cradle (not shown).

With tongs or a forked lever arrangement (not shown) the rods 1 arestarted one at a time by hand through the first air ring 23 until therod l makes contact with the magnetic driven rolls [2 and I3. Theself-adjusting guide roller the number of Preece dips required.

The speed of the rod carries it against a stop at the end of theconveyer trough 42, where a kicker arrangement (not shown) operatedautomatically or by handdischarges the rod into the water quenching tank40.- The coating is hardened and brightened by this quenching operation.The galvanized rods are then lifted by hand from the quenching tank 40and further processed for shipment.

The spinning of the galvanized rods in this manner results in averyuniform coating. Rods which have not been spun show coatings ofexcessive thickness on their lower surfaces, due' to gravity, and thinand inadequate coatings on their upper portions. The combination of theair rings with the spinning action of the skewed rolls automatically andquickly removes excess spelter from the threaded ends, and eliminatesthe extra step and added labor of cleaning the threads by bumping.

An even more important advantage is that the coating produced is a greatdeal more adherent and ductile than any hot-dip coating for sucker rodsheretofore known. Rods galvanized according to my invention have beensubjected to repeated and severe tensile tests withv out the coatingflaking or cracking off, and even a bend test gave only minor cracks inthe coating which were not especially detrimental because of the natureof the protection afforded by the electropositive zinc coating.

Although I have thus shown and described my invention in considerabledetail, I do not wish to be limited strictly to the exact and specificdetails shown and described, but I may also use such substitutions,modifications, or equivalents thereof as are embraced within the scopeof the invention or as are pointed out in the appended claims.

Having thus described my invention, what I claim as new and useful anddesire to protect by Letters Patent is:

.1. An apparatus for producing uniform ductile coatings on rods and thelike coated with molten metal, comprising a plurality of aligned airrings for smoothing the coating and making uniform the coatingthickness, and means for rapidly advancing and spinning the rod throughthe air rings.

2. An apparatus for producing uniform ductile coatings on rods and thelike coated with molten metal, comprising a plurality of aligned airrings for uniformly removing excess metal and rendering the remaindersmooth and even, and conveying mechanism adapted to spin the rod in thecourse of travel in a line substantially coinciding with the center ofthe air rings.

3. An apparatus forproducing uniform ductile coatings on rods and thelike coated with molten I metal, comprising a plurality of driven rollshavand advanced by the rolla having their axes skewed in relation to the.direction of travel of the coated rod, means for rotating said rollsmeans for supplying a heated fluid under pressure, and meansfordirecting said fluid under pressure against and around the peingtheir axes inclined to the line of travel of the idle roller toaccommodate different sizes 'ofriphery of the coated rod.

5.- An apparatus for producing uniform ductile coatings on rods and thelike coated with molten metal, comprising a plurality of hollow ringsperforated and adapted for directing Jets of fluid with substantialuniformity about the circum; i'erence of the rod,-and'spinning andconveying means comprising a series of skewed driven rolls one or moreof which are magnetized.

6. An apparatus for producing uniform coatings on threaded rods .and thelike coated with molten metal,'comprising a pair of spaced air.

' J 8. An apparatus 7. An apparatus for producing uniform coatings onhot-metal coated sucker rods or the like,-

comprising a pair of skewed magnetic rolls for advancing-and spinningthe coated sucker rods, a pair of adjacent air rings for smoothing andevening the coating on the sucker rods, an idle roller for. directingthe sucker' rods through the air rings, and means for manually adjustingthe sucker rods. l

for producing uniform ductile coatings on rod-like metal articlescomprising a pair of aligned air rings, and a pair of skeweddrivenmagnetic rolls situated therebetween.

9. An apparatus for producing uniform ductile coatings on rod-like metalarticles comprising a pair of aligned hollow rings adapted for .thepasrings suitably perforated for delivering a stream of air onto thecoated surface atan angle of approximately 45 to the plane of saidsurface to wipe excess coating metal therefrom-a pair of skewed drivenrolls therebtween each having a magnetizable periphery, coil windings inalignment with said rolls, a magnetic circuit energized by said coilwindings and including said rolls, and guide means for insuring theproper contact and direction of the coated rod as it is rotated sagetherethrough oi the coated article, each of said rings having a circularseries of openings directed toward the article, meansfor supplying aheated fluid air to the pair of hollow rings, and

a pair of driven magnetic rolls situated between the aligned hollowrings in skewed relation thereto for simultaneously rotating andconveying the rod-like article through the rings,

10. An apparatus for producing uniform ductil coatings On'hOt-dipgalvanized sucker rods comprising a pair of aligned air rings, a pair ofmotor'driven magnetized rolls skewed with respect to the common centerline of the air rings and placed between said, air rings for spinningthe rods while advancing said rods therethrough, andan idle guide rollplaced between and above the magnetized skew rolls to assist in aligningthe rods passed through the apparatus. I

ALLEN S. MOORE.

